Container safety closure

ABSTRACT

In combination, a safety container and cap assembly, the container having an elongated neck with at least two sets of threads of opposite pitch with respect to each other, one arranged proximally and one arranged distally with respect to the container, the cap having at least two sets of threads of opposite pitch with respect to each other, one arranged proximally and one arranged distally with respect to the cap complementary to and engageable with the respective sets of threads of the container, the set of threads proximal to the container having a greater diameter than that of the set of threads distal to the container, thereby permitting the distal threads of the cap to clear the distal threads of said container, the sets of threads of the container and the cap being sufficiently spaced apart so that only one set of complementary threads are engageable at one time.

United States Patent [191 Kramb et al.

1 1 CONTAINER SAFETY CLOSURE [75] Inventors: Kenneth D.-Kramb, Portage; Walter J. Isabell, Kalamazoo, both of Mich. [73] Assignee: K.I.C. Incorporated, Portage, Mich. [22] Filed: Mar. 16, 1973 [21] Appl. No; 342,274

3,269,576 8/l966 Law 3,690,496 9/1972 Gibson 3,734,332 5/1973 Grulich 215/9 3,784,045 1/1974 Komendowski 22(1/39 R X Primary Examiner-Herbert F. Ross Attorney, Agent, or Firm-Gordon W. Hueschen 5 7 ABSTRACT In combination, a safety container and cap assembly, the container having an elongated neck with at least two sets of threads of opposite pitch with respect to each other, one arranged proximally and one arranged distally with respect to the container, the cap having at least two sets of threads of opposite pitch with respect to each other, one arranged proximally and one arranged distally with respect to the cap complementary to and engageable with the respective sets of threads of the container, the set of threads proximal to the container having a greater diameter than that of the set of threads distal to the container, thereby permitting the distal threads of the cap to clear the distal threads of said container, the sets of threads of the container and the cap being sufficiently spaced apart so that only one set of complementary threads are engageable at one time.

10 Claims, 5 Drawing Figures CONTAINER SAFETY CLOSURE BACKGROUND OF THE INVENTION 1. Field of the Invention.

This invention relates to containers such as bottles and closures therefor such as caps, and more particularly refers to a combination of a container and safety closure designed to contain materials which may be dangerous or hazardous to individuals, particularly to children.

Containers such as bottles utilized for medicine or hazardous chemicals are commonly provided with a screw cap or a snap-on cap. Such closures may be readily opened even by children. Some attempts to provide safety closures which may be opened only with difficulty have been provided, for example in US. Pat. Nos. 3,430,796, 3,630,403, and 2,960,247. However, such disclosed containers have not been entirely satisfactory either because they are too easily opened by children, or because their cost of manufacture is excessive.

SUMMARY OF THE INVENTION It is accordingly an object of the invention to provide an improved safety container and closure which are too complicated to be manipulated and opened by small children but which can be readily opened by adults. It is an additional object to provide a safety container and closure which may be readily fabricated from inexpensive plastic materials. Still other objects will readily present themselves to one skilled in the art upon reference to the ensuing specification, the drawing, and the claims.

The present invention provides a container and safety closure each of which is provided with two sets of threads of opposite pitch, the sets of threads of the cap being complementary to the sets of threads of the container, the sets of threads being so spaced apart that only one set is engageable at a given time. Consequently, in order to remove the cap, it is necessary to turn the cap first in one direction until one set of threads are engaged and cleared, and then to turn the cap in the other direction to engage the second set of threads and to continue until the second set of threads are disengaged, permitting the cap to be removed.

BRIEF DESCRIPTION OF THE DRAWING In the drawing,

FIG. I is a side elevational view partly in section of the container and cap of the invention with the cap in closed position.

FIG. 2 is an enlarged fragmentary sectional view showing one set of threads disengaged and the other set about to be engaged.

FIG. 3 is an enlarged fragmentary sectional view showing the second set of threads engaged.

FIG. 4 is an enlarged fragmentary sectional view showing the cap entirely disengaged.

FIG. 5 is an enlarged fragmentary view showing another embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a safety container and closure assembly is shown comprising a container 11 and a cap 12. The container has a bottom 13, a cylindrical side wall 14, and a neck 15. The container may be formed of any suitable material such as glass, plastic materials such as polyethylene, polypropylene. styrene, nylon, or other plastic materials commonly used. Additionally, metals such as steel, zinc, copper. etc. may be used where appropriate. The cap 12 has a top wall 16 and a cylindrical side wall 17.

The neck 15 of the bottle is provided with two sets of threads of opposite pitch, a proximal thread set 18 which is preferably a left-handed thread, and a distal thread set 19 which is preferably a right-handed thread. The cap 12 is also provided with two sets of threads, a proximal thread set 20 which is preferably a righthanded thread and complementary to and adapted to engage the distal thread set 19 of the container neck 15, and a distal thread set 21 which is preferably a lefthanded thread and is complementary to and adapted to engage the proximal thread set 18 of the container neck. The cap is also provided with a recess 22 adapted to permit the side wall 17 of the cap to clear the thread set 18 of the container neck. Additionally, the distal thread set 21 of the cap is spaced sufficiently from the proximal thread set 20 in order to permit the thread sets 18 and 21 to clear and become disengaged before the thread sets 19 and 20 are engaged when closing the container, and upon opening the container, to permit the thread sets 19 and 20 to become disengaged before the thread sets 18 and 21 become engaged. This results from the fact that the two sets of threads are of opposite pitch, and cannot be engaged at the same time as this would render the structure inoperable.

The completely closed position of the container 11 and cap 12 is shown in FIG. 1. In order to remove the cap, the cap is rotated counterclockwise until the thread sets 19 and 20 are completely disengaged, as shown in FIG. 2. The cap is then lifted a further distance until the thread set 21 encounters the thread set 18. While still applying an upward force, the cap is now rotated clockwise, causing-the thread set 21 to engage the thread set 18, asshown in FIG. 3. Clockwise rotation of the cap is continued until the thread set 21 completely clears the thread set 18 and becomes disengaged, permitting the cap to be removed, as shown in FIG. 4. In order to replace the cap, the cap is again placed over the neck of the bottle until the thread set 21 engages the thread set 18. The cap is then rotated counterclockwise until the thread sets 18 and 21 become disengaged. The cap is then pushed downward until the thread set 19 engages the thread set 20. The cap is then rotated clockwise until the end 23 of the bottle neck engages the top wall 16 of the cap, or a gasket which may be inserted therebetween. In the embodiment shown, the initially encountered thread set is designed to have left-handed threads and the finally engaged thread sets are designed to be right-handed threads. Alternatively, this could be reversed, with the final thread set being left-handed and the initial thread set being right-handed.

FIG. 5 illustrates another embodiment of the invention comprising an assembly 26 of a container 27 and a cap 28. The container 27 has a neck 29 at one end, and the cap 28 is comprised of a top wall 30 and a cylindrical side wall 31. The neck 29 is provided with a pair of thread sets, a proximal thread set 32 and a distal thread set 33. The cap is provided with a pair of thread sets including a proximal thread set 34 and a distal thread set 35. The distal thread set 33 of the neck 29 and the proximal thread set 34 of the cap are complementary and engageable with each other, preferably being left-hand threads. The proximal thread set 32 of the neck and the distal thread set 35 of the cap are complementary and engageable with each other and are preferably right-hand threads. A recess 36 is provided in the wall of the neck 29 to permit the thread set 34 to clear the wall as it moves up and downyAdditionally, the diameters of the thread sets 33 and 34 are smaller than those of the thread sets 32 and 35 to per.- mit the thread set 35 to clear the thread set 33 when the cap is removed. A conventional gasket 38 of a material such as cork, paper, or metal may be interposed between the end of the container 37 and the cap.

In order to remove the cap 38, it is rotated counterclockwise until the thread sets 32 and 35 are disengaged. The cap is then lifted further until the thread set 34 encounters the thread set 33. While maintaining upward force, the cap is then rotated clockwise, the thread set 34 engaging the thread set 33 and traveling over the thread set until it disengages on the other side. The cap may then be removed. To reapply the cap, it is placed over the neck 29 until the thread set 34 encounters the thread set 33. The cap is rotated counterclockwise until the thread set 34 passes below the thread set 33. The cap is pushed downward until the thread set 35 encounters the thread set 32. The cap is then rotated clockwise until the two thread sets completely mesh and the end of the neck 37 engages the top wall 30 of the cap or the gasket 38 placed therebetween.

As may be seen in FIGS. 1-5, the thread sets of both embodiments shown must be so arranged that both of the thread sets on the container neck are male threads and both of the thread sets on the cap are female threads.

Since one pair of thread sets are right-handed and the other left-handed, sufficient space must be provided between the proximal thread set 32 and the distal thread set 33 of the container so that one thread set is disengaged when the other is engaged, thereby insuring that only one pair of complementary thread sets can be engaged at any given time. This is required for operability because the thread sets are of opposite pitch.

The safety container and closure assembly of the present invention has a number of advantages over those disclosed in the prior art. First, it requires a somewhat complicated procedure for removing the cap from the container, thereby preventing young children from readily removing the cap. The requirement of using two separate counter-directed motions for removing the cap also provides awarning to an adult that contents may be hazardous. The structures may be readily formed by conventional means such as molding, and may be made of any of a large number of materials. Additionally, both the cost of the materials and the cost of fabrication are relatively small. It is to be understood that the invention is not to be limited to the exact details of structure, materials, or procedures shown and described, as obvious modifications and equivalents.

will be apparent to one skilled in the art.

We claim:

1. In combination, a safety container and cap assem bly comprising: i

l. a container having an open-ended neck, said neck having provided on the outer surface thereon:

a. a proximally arranged male thread set, and

b. an axially spaced distally arranged male thread set of opposite pitch and smaller diameter with respect to said proximally arranged thread set,

2. a cap having a top wall and a cylindrical side wall,

said cap having provided on the inner surface of said side wall:

a. a proximally arranged female thread set complementary to and adapted to engage the distally arranged thread set of said neck, and

b. an axially spaced distally arranged female thread set of opposite pitch with respect to said proximally arranged thread set (2a) and complementary to and engageable with the proximally arranged thread set of said neck,

the axial spacing of the respective threads on said cap being greater than the axial spacing of the respective threads on said neck, the thread sets of said neck and said cap being so arranged that only one complementary pair of thread sets of said neck and said cap can be engaged at any given time, whereby removal of said cap requires rotation first in one direction and then in the other.

2. A safety container and cap assembly according to claim 1, wherein the distal thread set on said neck and the proximal thread set on said cap are both righthanded, and the proximal thread set of said neck and the distal thread set of said cap are both left-handed, and whereby final closure is accomplished by engagement of the distal thread set of said neck and the proximal thread set of said cap.

3. A safety container and cap assembly according to claim 2, wherein a recess is provided in the side wall of said cap intermediate the proximal and distal thread sets thereof to permit the proximal thread set of said neck to travel therein.

4. An assembly according to claim 1, wherein the distal thread set of said neck and the proximal thread set of said cap are left-handed and the proximal thread set of said neck and the distal thread set of said cap are right-handed, and whereby final closure is accomplished by engagement of the proximal thread set of said neck and the distal thread set of said cap.

5. An assembly according to claim 1, wherein said container is formed of glass.

6. An assembly according to claim 1, wherein said container is formed of a plastic material.

7. An assembly according to claim 1, wherein said cap is formed of a plastic material.

8. An assembly according to claim 1, wherein said container is formed of metal.

9. An assembly according to claim 1, wherein a gasket is provided in said cap for sealing the open end of said container.

10. An assembly according to claim 4, wherein the portion of said neck intermediate the thread sets provided thereon is recessed to permit the proximal thread set of said cap to travel therein. 

1. In combination, a safety container and cap assembly comprising:
 1. a container having an open-ended neck, said neck having provided on the outer surface thereon: a. a proximally arranged male thread set, and b. an axially spaced distally arranged male thread set of opposite pitch and smaller diameter with respect to said proximally arranged thread set,
 2. a cap having a top wall and a cylindrical side wall, said cap having provided on the inner surface of said side wall: a. a proximally arranged female thread set complementary to and adapted to engage the distally arranged thread set of said neck, and b. an axially spaced distally arranged female thread set of opposite pitch with respect to said proximally arranged thread set (2a) and complementary to and engageable with the proximally arranged thread set of said neck, the axial spacing of the respective threaDs on said cap being greater than the axial spacing of the respective threads on said neck, the thread sets of said neck and said cap being so arranged that only one complementary pair of thread sets of said neck and said cap can be engaged at any given time, whereby removal of said cap requires rotation first in one direction and then in the other.
 2. A safety container and cap assembly according to claim 1, wherein the distal thread set on said neck and the proximal thread set on said cap are both right-handed, and the proximal thread set of said neck and the distal thread set of said cap are both left-handed, and whereby final closure is accomplished by engagement of the distal thread set of said neck and the proximal thread set of said cap.
 2. a cap having a top wall and a cylindrical side wall, said cap having provided on the inner surface of said side wall: a. a proximally arranged female thread set complementary to and adapted to engage the distally arranged thread set of said neck, and b. an axially spaced distally arranged female thread set of opposite pitch with respect to said proximally arranged thread set (2a) and complementary to and engageable with the proximally arranged thread set of said neck, the axial spacing of the respective threaDs on said cap being greater than the axial spacing of the respective threads on said neck, the thread sets of said neck and said cap being so arranged that only one complementary pair of thread sets of said neck and said cap can be engaged at any given time, whereby removal of said cap requires rotation first in one direction and then in the other.
 3. A safety container and cap assembly according to claim 2, wherein a recess is provided in the side wall of said cap intermediate the proximal and distal thread sets thereof to permit the proximal thread set of said neck to travel therein.
 4. An assembly according to claim 1, wherein the distal thread set of said neck and the proximal thread set of said cap are left-handed and the proximal thread set of said neck and the distal thread set of said cap are right-handed, and whereby final closure is accomplished by engagement of the proximal thread set of said neck and the distal thread set of said cap.
 5. An assembly according to claim 1, wherein said container is formed of glass.
 6. An assembly according to claim 1, wherein said container is formed of a plastic material.
 7. An assembly according to claim 1, wherein said cap is formed of a plastic material.
 8. An assembly according to claim 1, wherein said container is formed of metal.
 9. An assembly according to claim 1, wherein a gasket is provided in said cap for sealing the open end of said container.
 10. An assembly according to claim 4, wherein the portion of said neck intermediate the thread sets provided thereon is recessed to permit the proximal thread set of said cap to travel therein. 